Risotto figures out that Doppio must be a Stand user that the boss trusts in deeply because he’s able to hear the noise from a certain Stand. Risotto then uses his Stand Metallic against him. Metallic is able to control magnetic force and attacks Doppio. Doppio uses the part of the boss’s power he received from him. While they’re fighting, Risotto realizes that Doppio’s personality and actions seem to be changing and he realizes exactly who Doppio is.
He was preparing for me 
to lose all this stamina!
!كان ينتظرني حتّى أخسر كلّ هذه اللّياقة
Er hat es darauf angelegt,
dass mir die Puste ausgeht!
Hizo todo eso para desgastarme.
Hizo todo eso para desgastarme.
c’étaient des préparatifs
pour m’épuiser !
Mi ha attaccato fin da subito
con lo scopo di farmi esaurire le energie!
Ele está me fazendo perder todas as minhas forças.
Он только того и ждёт —
 чтобы я остался без сил!